SKELETAL-MUSCLE CHANGES IN PATIENTS WITH CHRONIC HEART-FAILURE BEFOREAND AFTER TREATMENT WITH ENALAPRIL

To evaluate if enalapril treatment can influence skeletal muscle metab olism and histology we investigated 26 patients with congestive heart failure and 20 normal subjects. The patients were treated with enalapr il for 3 months in addition to diuretics and digitalis. Biopsies from the lateral vastus muscle were taken before and after treatment. Citra te synthetase, 3-hydroxyacyl-CoA dehydrogenase and phosphorylase activ ities were significantly decreased in the patients compared with contr ols. The number of capillaries per fibre and the number of capillaries surrounding each fibre were significantly decreased among patients. A fter 3 months of enalapril treatment functional class improved signifi cantly. The lactate dehydrogenase activity increased whereas the oxida tive enzymes did not change significantly. The type I, II and IIA fibr e areas increased significantly after enalapril treatment. We conclude that patients with chronic heart failure have decreased activity of o xidative enzymes and of phosphorylase in skeletal muscle. They also ha ve decreased capillarization in skeletal muscle. These changes were no t influenced by enalapril treatment,The increase in muscle fibre area seen after enalapril treatment could be due to increased physical acti vity. The cause of increased muscle lactate dehydrogenase activity aft er enalapril treatment needs further investigation.